\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=newest}
\usetikzlibrary{pgfplots.groupplots}
\begin{document}
  \begin{tikzpicture}
    \pgfplotsset{
      table/x index={1},
      table/y index={2},
      table/header={true},
    }
    \begin{groupplot}
      [
        group style = {group size=2 by 1},
        colormap/jet,
        enlargelimits=false,
        grid = major,
        xtick=\empty,
        ytick=\empty,
        %      xtick={2.5,5},
        %      ytick={0,2.5,...,5},
        %      x unit = {\deg}
      ]
      \nextgroupplot
      [
        only marks, 
        scatter,
        scatter src=explicit,
        clip = false,
      ]
      \addplot
        table 
        [point meta=\thisrowno{3}/100]
        {/home/mrajner/src/grat/doc/figures/interpn1.dat};
      \addplot+
        [ mark size=0.41em ]
        table 
        [
          point meta=\thisrowno{2}/100,
          x index=0,
          y index=1,
          header = false,
        ]
        {/home/mrajner/src/grat/doc/figures/interp1.dat};
      \nextgroupplot
      [only marks, 
        scatter,
        colorbar,
        scatter src=explicit,]
      \addplot
        table
        [point meta=\thisrowno{3}/100 ] 
        {/home/mrajner/src/grat/doc/figures/interpl1.dat};
      \addplot+
        [mark size=0.41em]
        table
        [
          point meta=\thisrowno{2}/100,
          x index=0,
          y index=1,
          header = false,
        ]
        {/home/mrajner/src/grat/doc/figures/interp1.dat};
    \end{groupplot}
  \end{tikzpicture}
\end{document}
